1. Field of the Invention
The invention relates to a circuit board connector and to a method of assembling it.
2. Description of the Related Art
Japanese Unexamined Utility Model Publication No. 61-60486 and FIG. 8 herein disclose a circuit board connector that is mountable on a circuit board. With reference to FIG. 8, the connector has a housing 1 made of synthetic resin and a receptacle for receiving a mating connector. Substantially L-shaped terminal fittings 2 are arranged to penetrate the housing 1. One end of each terminal fitting 2 projects into the receptacle while the other end projects out of the housing 1.
This type of connector is produced by inserting the terminal fittings 2 through insertion holes to provide communication between areas inside and outside the receptacle. Each terminal fitting 2 is pressed into the through hole and fixed by a frictional force between the terminal fitting 2 and the inner wall of the through hole. The terminal fittings 2 are pressed into the through holes and are abraded against the inner walls of the through holes. Thus, the inner walls may be scratched and produce chips. Plating is applied to the terminal fittings 2 to achieve a satisfactory electrical connection with a mating connector. However, some plating may be scraped off by the friction between the terminal fittings 2 and the inner walls of the through holes. As a result, the terminal fittings 2 typically are inserted into the through hole from the receptacle side. Thus, there has been no problem caused by the chips since the chips on the inner walls of the through holes are discharged to the outside of the connector housing 1 through the insertion holes open to the outside of the connector housing 1.
A recent demand for a simplified production process now requires terminal fittings 2 to be inserted from outside the housing 1 into the receptacle. However, chips scratched off by the insertion of the terminal fittings 2 in this opposite direction now are discharged into the receptacle. The chips can be squeezed between the mating connector and the surface of the receptacle. Thus, the mating connector and the circuit board connector cannot be connected at a proper position. In an extreme case, this may lead to a contact error between the mating terminals.
The invention was developed in view of the above problem and an object thereof is to provide a circuit board connector that prevents a connection error with a mating connector.
The invention relates to a circuit board connector with a housing that has a receptacle for receiving a mating connector. Through holes extend through a rear wall of the receptacle and provide communication between areas inside and outside the receptacle. The connector further includes terminal fittings that are introduced through the through holes from the outside towards the receptacle of the housing. The rear wall of the receptacle is formed with recesses by widening at least part of the inner peripheral surfaces of the through holes. Thus, even though the terminal fittings are inserted from the rear side of the housing to the inside of the receptacle, the chips stay in the recesses and do not enter the receptacle. As a result, a connection error with the mating connector and a contact error between mating terminals resulting from the chips squeezed between the mating connector and the receptacle are prevented.
At least one bulge may bulge out in widthwise direction at a connection leg of each terminal fitting and projects from the housing. The bulge can be fit into a circuit board. Thus, the circuit board connector can be fixed to and electrically connected with a printed circuit board by inserting the connection legs into mount holes in the printed circuit board. As a result, operation steps such as soldering become unnecessary and the operation is more efficient.
The terminal fitting preferably comprises one or more pressing portions for engaging and biting into the through hole. Accordingly, the terminal fittings can be held easily and efficiently be in the housing.
The front of each pressing portion, as seen in an inserting direction, preferably is slanted. Accordingly, the slanted front guides the terminal fittings substantially to a proper position so that operational efficiency is improved.
The through holes preferably are substantially in the centers of the corresponding recesses.
The terminal fittings may comprise stoppers for engaging stopper receiving portions of the housing to stop the insertion of the terminal fittings into the through holes. Insertion of the terminal fittings can be stopped appropriately, thereby improving their positioning with respect to the housing.
A front portion of the terminal fittings as seen in an inserting direction preferably has outer dimensions smaller than the corresponding inner dimensions of the through holes and plating preferably is applied to the front portion. Accordingly, the plating will not be scratched or damaged during the insertion of the terminal fitting into the through holes.
A connecting leg of the terminal fitting projects back from the connector housing and preferably is bent at an angle to the inserting direction.
The invention also relates to a method of assembling a circuit board connector. The method comprises providing a housing having a receptacle into which a mating connector can be fit. A wall of the receptacle of the housing has through holes that provide communication between the inside and the outside of the receptacle. The method then comprises mounting terminal fittings into the housing by introducing the terminal fittings through the through holes from the outside of the housing. The wall of the receptacle is formed with recesses by widening at least part of the inner peripheral surfaces of the through holes.
At least one bulge preferably bulges out in width direction at a connection leg of each terminal fitting that projects from the housing. The bulge then is inserted into a circuit board.
The mounting step preferably comprises a step of bringing pressing portions of the terminal fitting into engagement with the through hole so that the pressing portions bite into the through hole.
The insertion of the terminal fittings preferably is guided by a slanted front part of the pressing portions as seen in an inserting direction.
The insertion of the terminal fittings into the through holes preferably is stopped by bringing stoppers on the terminal fittings into engagement with corresponding stopper receiving portions of the housing.
These and other features and advantages of the invention will become more apparent upon reading the following description of preferred embodiments and accompanying drawings. Even though embodiments are described separately, single features may be combined to additional embodiments.